--          This file is part of SmartEiffel The GNU Eiffel Compiler.
--       Copyright (C) 1994-2002 LORIA - INRIA - U.H.P. Nancy 1 - FRANCE
--          Dominique COLNET and Suzanne COLLIN - SmartEiffel@loria.fr
--                       http://SmartEiffel.loria.fr
-- SmartEiffel is  free  software;  you can  redistribute it and/or modify it
-- under the terms of the GNU General Public License as published by the Free
-- Software  Foundation;  either  version  2, or (at your option)  any  later
-- version. SmartEiffel is distributed in the hope that it will be useful,but
-- WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
-- or  FITNESS FOR A PARTICULAR PURPOSE.   See the GNU General Public License
-- for  more  details.  You  should  have  received a copy of the GNU General
-- Public  License  along  with  SmartEiffel;  see the file COPYING.  If not,
-- write to the  Free Software Foundation, Inc., 59 Temple Place - Suite 330,
-- Boston, MA 02111-1307, USA.
--
class E_VOID
   --
   -- Handling of the Eiffel `Void'.
   --

inherit EXPRESSION

creation make

feature

   start_position: POSITION

   is_void: BOOLEAN is true

   is_writable: BOOLEAN is false

   is_current: BOOLEAN is false

   is_result: BOOLEAN is false

   is_static: BOOLEAN is true

   static_value: INTEGER is 0

   to_integer_or_error: INTEGER is 0

   is_pre_computable: BOOLEAN is true

   is_manifest_string: BOOLEAN is false

   can_be_dropped: BOOLEAN is true

   use_current: BOOLEAN is false

   c_simple: BOOLEAN is true

   start_lookup_class: BASE_CLASS is do end

   bracketed_pretty_print, pretty_print is
      do
         pretty_printer.put_string(as_void)
      end

   to_string, to_key: STRING is
      do
         Result := as_void
      end

   isa_dca_inline_argument: INTEGER is -1

   dca_inline_argument(formal_arg_type: E_TYPE) is
      do
         mapping_c_arg(formal_arg_type)
      end

   assertion_check(tag: CHARACTER) is do end

   afd_check is do end

   safety_check is do end

   mapping_c_target(target_type: E_TYPE) is
      do
	 check false end
      end

   mapping_c_arg(formal_arg_type: E_TYPE) is
      do
         compile_to_c
      end

   short is
      do
         short_print.hook_or(as_void,as_void)
      end

   short_target is
      do
         short
         short_print.a_dot
      end

   collect_c_tmp is do end

   compile_to_c is
      do
         cpp.put_string(fz_null)
      end

   c_frame_descriptor(format, locals: STRING) is do end

   compile_target_to_jvm, compile_to_jvm is
      do
         code_attribute.opcode_aconst_null
      end

   jvm_branch_if_false: INTEGER is
      do
	 check false end
      end

   jvm_branch_if_true: INTEGER is
      do
	 check false end
      end

   compile_to_jvm_into(dest: E_TYPE): INTEGER is
      do
         Result := 1
         compile_to_jvm
      end

   result_type: TYPE_NONE is
      local
         unknown_position: POSITION
      once
         create Result.make(unknown_position)
      end

   to_runnable(ct: E_TYPE): like Current is
      do
         Result := Current
      end

   stupid_switch(run_time_set: RUN_TIME_SET): BOOLEAN is
      do
         Result := true
      end

   print_as_target is
      do
	 check false end
      end

   precedence: INTEGER is
      do
         Result := atomic_precedence
      end

   jvm_assign_creation, jvm_assign is
      do
	 check false end
      end

feature {NONE}

   make(sp: like start_position) is
      require
         not sp.is_unknown
      do
         start_position := sp
      ensure
         sp = start_position
      end

end -- E_VOID